| 摘要 |
Natural or synthetic polyamide fibres are simultaneously bleached and dyed with a dye liquor containing a water-soluble dye, a water-soluble salt of a 4-valent sulphur oxy-acid, e.g. sodium hydrogen sulphite and sodium hydrogen pyrosulphite, and a compound capable of forming stable, water-soluble, colourless complexes with metal ions in the dyebath, e.g. tri- and/or tetrasodium ethylenediamine tetra acetate (others are specified). The process may apply to wool (especially), silk, nylon and mixed fabrics containing them. The dyes are preferably acid dyes and the dyebath may further contain an acid as well as known auxiliaries. Dyeing may preferably be carried out at 85 DEG C. Examples are given. |
